Sheet feeding



F. R. SCHMITT `lune 7, 1949.

SHEET FEEDING Original Filed Oct. '7, 1942` @ad ATTORNEYS Patented June 7, 1949 NITE!) STAT SHEET FEEDING Frank n. sohiufitt, Hollis, N. assigner, llyiileshe assignments, to Aerovox Corporation, New Bedford, Mass., a corporation "of Massahsetts Original application October 7i 1942Serimal pl 461,238.. Divided vand this applieatib 6i 1947, Serial No. 746,368

(Cl. ilil) y 9 Claims. v 1

The present invention is concerned with the art of sheet feeding and more particularly with magazines for stacked sheets and the control appurtenances thereof, 'and is especially useful with, though not limited to, the testing of 'mica sheets used as a dielectric in electrostatic capacitors.

In order that la largenumber of mica sheets may be stacked in a magazine lit is desirable that they be maintained under compression. However, by reason of the resiliency of 'mica sheets, there would be danger of many of them, when under such compression, being catapulted from the top of the magazine unless some means were provided to retain them therein. As the top of the magazine must be open to allow the mica sheets to be removed from or inserted therein in the successive handling thereof, the retaining means must be constructed so that there will be no restraint on the 'mica stack when it is desired to remove or insert a mica sheet in the magazine as the case may be and such restraint must be restored after the sheet has been removed or inserted.

It is among the objects oi this invention to provlcle a magazine of the above type which will maintain a stack of inic'a sheets under compression, which will retain the stack in the magazine and which Will automatically release the retaining means when required.

It is among other objects of this invention to provide a magazine in which the stack regardless of its height Will be reliably urged into engagement of its upper sheet with the suction head of the sheet feeding mechanism when the latter is in stack engaging position and Which will reliably restrain the stack against being catapulted from the magazine during the intervals that the suction head is not in engagement With the stack.

It is among other objects of this invention to provide a mount for said magazine which is simple, rugged and quick to manipulate for instantly yet securely replacing an empty supply magazine or a iille'd collector magazine.

In order 'more fully to describe the embodiment herein chosen to illustrate my invention it Will be shown and described as applied to the mica sheet classifying machine shown in the parent application Serial No. 461,238, filed October '7, 1942, now Patent Number 2,425,347. of Whieh this application is a division.

In the accompanying drawings in which is shown one of various possible embodiments of the several features of my invention,

Fig. 1 is a fragmentary 'fr'r'it elevational viW of a mica classifying machine utilising the device herein, n

Fig. 2 `ls a fragmentary side elevational view en a larger soaleof 'the supply magasine vand Fig. s is a longitudinal cross sectional view yon a larger scale showing the 'loonstluction of the supply magazine. A l

Referring now to the drawings, the classify-lhs machine has a bed llbohioh supports the operating mechanism inoludihgth supply magazine l2 containing the sheets to yhe tested and -olasslned the testing block lt, which 'has been fully de-j sented in my above identified application and the collector magazine I4 for thesheets found to be satisfactory orseleotedgoh testi inasmuch as the supply magazine and oolleotoi Iirlagazine are substantially identit-lin oohstiuotioh, only the 'former Willits-described ih detail, similar rei-y erehoe numerals 'being applied to identical parts ofthe collector magazine for ease ih understandlng.

Magazine l2 is'open at both ends and has ah inwardly turned hangs l5 at the hottoih thereof, forming a shoulder which limits the downward motion of the follower lt therein As best shown ifi rl-gs. 2 and s, iolloo'e l is oroierahlyspnhg urged by mechanism more fully ,described here; ihaiter, which servesto maintain, the stools ih elevated position within 'the magazine.

For convenience, the supply Aand oolleotor magazines may he irlterchahged. However, sii/loe there 'is no need idr urging the sheets upward in the collector magazine, bearing in mind4 that the sheets are to te delivered thersinto rather than picked oli therefrom, it is sul'lloieht to 'provide a friction follower ls" iii said magazine, which is pushed downward asshets pressed thefeihto ifi the nallr f b' iij jleSefl'lSl The sheets from the supply magazine l2 are successively to be picked olif therefrom by 'resort to a pick up suction head l1 normally registering with the supply magazine I2, as' shown ih Figs. 1 and 3, and transported forIl-aying the vsheet upon the testing block B 'he pick up head'l'l is constrained to have a constant reciprocating move ment from the topof the supply magazine l2, Where it picks ilp a sheet, to the top of the testing block I3 where it deposits the sheet. A selector suction head l has a reciprocating movement from the top of the testing block i3 where it picks up the tested sheet and carries it to the top of the collector magazine lt there it dopo-sits the sheet. l

It lwill of oo' s'e lle understood that the suction heads' l and I8' "Inu't be lifted free oi the niagazines and testing block before the heads can move laterally from the supply magazine l2 to the testing block I3, and from the testing block i3, and from the testing block I3 to the collector magazine I4 and cannot descend into the magazines until the conclusion of the lateral tra-nsfer or transport movement. To bring this action about, it has been found advantageous to move the two suction heads I'I and I8 vertically up and down in their lifting and delivery action and to transport them horizontally in the intervening travel between the stations of pick up and delivery.

As the construction and operation of the suction heads II and I8 together with the control mechanism therefor has been fully described in the parent copending application above identied, it will not be described in more detail herein, except insofar as such construction and operation forms part of the present invention.

Means are provided to function upon release of the pick up and selector heads after they have pressed downward upon the stacks in the course of operation for preventing catapulting of the compressed resilient mica sheets from the magazines in which they are stacked.

A sleeve 23 about the supply magazine I2 (see Figs. l and 3) is equipped with transverse pins 2I which serve as pivots for a pair of upstanding levers 22 and 23 that are pressed toward each other by a coil spring 24 connecting the upper ends of said levers and desirably anchored to cross pins 25 thereof. Pins 25 serve as pivots for clamping heads 2B, each equipped with a resilient shoe 21 desirably of rubber retained by said spring 24 to extend through corresponding slots 28 in the magazine I2 into engagement with the lateral edges of the sheets near the top of the stack. Lever 22 has a horizontal arm 23 at its lower end with a cross pin 33 extending through yoke 3I in the corresponding arm 29 on the lower end of lever 23. Lever 22 desirably has an oblique upper extension lug 32 in the path of movement of a screw head 33 on the extremity of a pilot rod 34 which is parallel to pick up suction head I'l and is adapted to move therewith. As the pick up head I 'I is urged downward into the supply magazine I2, the screw head 33 cams the oblique lug 32 of lever 22 out- Ward to release the shoe 21 from the stack of sheets in the magazine and through the transmission of arms 29 and 29' similarly to release the shoe on the other lever 23 so that as the pick up suction head I'I reaches the top of the stack, the shoes 27 no longer clamp the edges of the mica sheets. As head I'I engages the stack and is pressed downward thereon, the latter will be compressed correspondingly to urge the follower IS downward in the supply magazine. In the subsequent rise of head I1, the screw head 33 will release lug 32 of lever 22 and before the pick up head II has left the magazine, the lateral clamping shoes 21 will thus be urged back by spring 24 to grip the edges of the upper sheets in the stack so that the catapulting of sheets under the resilience of the compressed stack will not occur upon withdrawal of the pick up suction head I1 from the supply magazine I 2.

Inasmuch as the pick up suction head il has a fixed up and down stroke, it is important that the upper dielectric sheet in the supply stack be urged upward so as to assure engagement thereof with the suction head I 1, even though the supply in the stack nears exhaustion. To that end, follower I6 is provided with a rod 35 extending axially through a socket member 36 which supports the magazine I2. Said socket member 35 comprises an upper socket portion 6I, a lower socket portion 42 and an intermediate portion hub 52, whereas socket member 36 which supports the collector magazine I4 comprises only the upper socket portion and the hub portion, the latter two portions being identical to those of the supply magazine I2 and not shown in the drawings. Cross bar 37 is secured to the lower end of rod 35 by a nut 38, rod 35 having a washer 39 at its upper end which engages the underside of follower I6. A pair of long coil springs 4D anchored to the ends of cross bar 3l at their lower ends as at 4B', are connected to pins 4I protruding from the lower portion 42 of the magazine socket 35. It is desirable in this connection to have the upward thrust of the springs 4B occur only after the suction head i. has entered the magazine I2 and while the lateral shoes 27 are released and thus to preclude the exertion of lifting spring pressure on said stack when the suction head I7 is no longer in the magazine I2. If such expedient were not provided, the lifting spring pressure might be sumcient to break oi or crack the edges of the mica sheets grasped by the lateral shoes 2l.

To this end the rod 35 extends through an aperture 48 in a brake arm 43 pivoted to a lug 44 on the lower portion 42 of the magazine socket 35 and urged obliquely upward by a coil spring 45 anchored at one end to a cross pin 4G through the free end of said brake arm 43 and at the other end to a pin 41 in the lower portion 42 of said socket 36, so that the diagonally opposite edges of the aperture 48 in the brake arm 43 will grip the rod 35 and brake or lock the same against exertion of the springs 49.

Momentarily to release brake arm 43 at the desired instant, there is provided a cam lever 49 having an oblique lower cam end 50 engaging the cross pin 46 so that when the lever 49 is shifted to the right in Fig. 3 through but a small angle, the brake arm 43 will be pushed downward slightly to relax its grip upon the rod 35 which will thus be spring urged upwardly in magazine I2 for the desired purpose.

As the mechanism for pivoting lever 49 has been fully described in the parent application above identified, it will not be more fully described herein inasmuch as it forms per se no part of this invention.

Desirably the supply magazine I2 and the collector magazine I4 are removable from the bed of the machine for replacement. To this end, the hub 52 of socket 36 and 36' is provided with a reduced portion 52 therein, forming ilanges 54. The socket is laterally introduced through a corresponding slot 53 in the bed of the machine, the flanges 54 on the socket hub 52 engaging the faces 55 of said bed. Each socket is kept in place by a corresponding latch 56 pivoted at one end to the edge of the bed II to one side of the slot 53 and having a notch 51 at the opposite end thereof which straddles the shank of a screw 58 at the op-posite side of said slot.

The upper portion 6I of the socket has lateral slots 65, through which lateral studs 59 protruding outward from the lower part of the magazine are laterally introduced. The magazine is secured in place by the tightening of the nuts 62 that are threaded upon said studs.

The machine is also equipped with means for automatically interrupting the operating circuit when the supply magazine ls empty or when the collector magazine is full. To this end the fol lower I6 in the supply magazine l2 is brought into contact with a leaf spring 63 (Fig. 2)v which protrudes into the magazine through a slot 64 therein so that the follower I6 when it reaches its uppermost position closes a grounding circuit (not shown) which interrupts the operation of the machine.

In a similar Way the collector magazine I4 is provided with a contact spring, not shown, en gaging the corresponding follower I6" therein when the latter reaches the lower end of the mag'- azine, i. e., when the magazine is full. This connection will also cause the machine to stop when the collector magazine is filled.

In operating the machine with the magazines hereindescribed, it is desirable to have a supply of fully loaded sup-ply magazines and empty collector magazines on hand so that when a replacement magazine is needed, it may be quickly inserted in the socket without vany excessive delay in the operation of the machine.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. In an automatic machine for handling resilient sheets stacked under compression, a magazine, a follower in said magazine, a suction head near the upper part of said magazine, means imparting to said head a fixed vertical stroke to engage the top sheet of rthe stack, clamp means normally urged laterally to grip the upper part of the stack within the magazine, and means correlated with the movement of said head for opening said clamp when the head enters the magazine and for releasing said clamp for reclosure thereof prior to removal of the head from the magazine.

2. In an electrically operated machine for handling resilient sheets stacked under compression, a magazine, a follower in said magazine, a suction head near the upper part of said magazine, means imparting to said head a xed vertical stroke to engage the top sheet of the stack, clamp means normally urged laterally to grip the upper part of the stack within the magazine, means correlated with the movement of said head `for opening said clamp when the head enters the magazine and for releasing said clamp for reclosure thereof prior to removal of the head from the magazine, and means actuated by said follower to interrupt the operating circuit of the machine When the follower reaches the extremity of its movement in said magazine.

3. In an electrically operated machine for handling sheets, a supply magazine, a spring urged follower in said supply magazine to urge the sheets upward therein, a pick up head near the upper part of said magazine, means imparting to said head a fixed vertical stroke to pick up the uppermost sheet from the supply magazine, clamp means normally used laterally to grip the upper part of the stack Within the magazine, means correlated with the movement of said head for opening said clamp when the head enters the magazine and for releasing said clamp for re- 6 closure thereof prior to removal of the head from the magazine.

4. The combination set forth in claim 3in which means are provided near the top of said magazine under control of said follower anto matically to interrupt the `operating circuit of the machine when the supply magazine is empty.

5. In an electrically operated machine for handling sheet material, a collector magazine, -a follower in said collector magazine, a suction head near the upper part of said magazine, means imparting to said head a xed vertical stroke to deposit a sheet in said collector magazine, clamp means normally urged laterally to grip the upper part of the stack Within the magazine, means correlated with the movement of said head for opening said clamp when the head enters the magazine and for releasing said clamp for reclosure thereof prior to removal of the head from the magazine, and means near the ybottom of said magazine actuated by said follower to interrupt the operating circuit of the machine when the magazine is full and requires replacement.

6. In an automatic machine for handling sheets which are resilient when stacked under compression, a bed, a supply magazine rising therefrom, a follower therein having a rod extending therebelow, spring means urging said rod upward to lift a supply stack of sheets in said magazine, a pick up head near the upper part of said supply magazine, means imparting to said head a fixed vertical stroke to engage the top sheet of the stack and to pick the same up preparatory to transporting the same, means comprising a brake normally locking said rod against the impulse of said spring, clamp means laterally gripping the upper part of the stack within the magazine, and means for opening said clamp and releasing said brake when the head enters the magazine and for releasing said clamp and resetting said brake prior to removal of the head from the magazine.

7. In an automatic machine for handling resilient sheets which are stacked under compression, the combination of a bed, a carrying socket with a reduced hub removably mounted in a lateral slot in said bed, releasable means to retain the socket against shifting out of said slot, a magazine removably mounted in said socket, releasable means to retain said magazine in said socket, a follower in said magazine, a suction head near the upper part of said magazine, means imparting to said head a xed vertical stroke to engage the top sheet of the stack, clamp means urged laterally to grip the upper part of the stack within the magazine, and means correlated with the movement of said head for opening said clamp when the head enters the magazine and for releasing said clamp for closure thereof prior to removal of the head from the magazine.

8. In an automatic machine for handling resilient sheets which are stacked under compression, the -combination of a bed, a socket member having an upper socket portion, a lower socket portion and an intermediate reduced portion adapted to be releasably accommodated in a lateral slot in said bed, latch means for releasably locking the socket in said slot, a magazine in said upper socket portion, releasable means to retain said magazine in said socket, a follower in said magazine having a rod extending therebelow, spring means affixed to said lower socket portion urging said rod upward to lift a supply stack of sheets in said magazine, a pick up head near the upper part of said supply magazine, means imparting to said head a fixed vertical stroke to engage the top sheet of the stack to pick up the same preparatory to transporting the same, means comprising a brake supported on said lower socket portion normally locking said rod against the impulse of said spring, clamp means urged laterally to grip the upper part of the stack within the magazine, and means correlated with the movement of said head for opening said clamp and releasing said brake when the head enters the magazine and for releasing said clamp for closure thereof and releasing said brake prior to removal of the head from the magazine.

9. In apparatus of the character described, the combination of a bed, a supply magazine rising therefrom, a socket mounting the same upon said bed, a follower in said magazine, a rod through said socket, spring-urged means for pressing said rod upward against said follower to lift the stack of sheets in the magazine, a brake arm pivoted under said socket through which said rod extends, spring means urging said brake arm upwardly to clamp said rod and preclude the exertion of lifting spring pressure upon said stack,

clamp means upon said magazine including a pair of arms spring-urged toward each other, each having a shoe extending through a corresponding slot in the magazine for resilient pressure engagement of the sheet edges near the upper part of the magazine, a pick up head for engaging a sheet at the top of the magazine, means for releasing the brake arm to cause the stack to be spring-urged upward against the head, and means for causing both said clamp means and said brake arm to be restored to operativeness prior to the withdrawal of the head from the magazine.

FRANK R. SCHMITT.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 239,543 Planche Mar. 29, 1881 2,069,246 Hanson Feb. 2, 1937 2,402,357 Bates June 18, 1946 2,425,347 Schmitt Aug. l2. 1947 

